The present invention relates to a process and to an apparatus for the heat treatment of meals.
The invention relates to a process for operating an apparatus for the heat treatment of meals which has a cooking area.
Such apparatuses can be operated in various operating modes, particularly with hot air or steam only. It is also possible to operate such apparatuses with a mixture of steam and hot air.
Generally, particular cold food or meals are treated by steaming. Deep-frozen food or meals are thawed and heated in this way. Other preparation processes such as boiling, roasting or baking are carried out in hot air operation or in a so-called combination steaming operation, in which the food is subject to the action of a mixture of steam and hot air. On changing between these different operating modes, certain inadequacies occur in practice. Particularly when operating the apparatus in hot air operation, temperatures well above 100.degree. C. prevail in the cooking area. If, following such a hot air treatment, food or meals introduced afresh into the cooking area are to be treated by means of steam, then, because of the still very high temperatures prevailing in the cooking area, such food is subject to crust formation or burn at specially exposed points. This more particularly applies to those portions of the meals or food adjacent to the cooking area walls.
To avoid the aforementioned inadequacies, the cooking area door is normally kept open until an adequate cooling has taken place. However, frequently the necessary cooking phase on passing between two operating modes, e.g. passing from hot air operation to steaming, is overlooked, so that food subsequently introduced is affected in the aforementioned manner. However, if a suitable time is allowed to pass before introducing the new meals or food into the cooking area it is very difficult for an operator to establish when the cooking area has cooled sufficiently to enable them to be introduced.
In view of the aforementioned inadequacies of the known process for operating an apparatus having a cooking area, the process problem of the present application is to provide a process for operating an apparatus having a cooking area, which permits a problem-free change between different operating modes of such an apparatus.